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52
53 package com.go.trove.io;
54
55 import java.io.*;
56 import java.util.Set  ;
57 import java.util.HashSet ;
58
59
68 public class FastCharToByteBuffer implements CharToByteBuffer, Serializable {
69 private static final int TEMP_BUF_LEN = 512;
70 private static final Set SUPPORTED_ENCODINGS;
71
72 static {
73 SUPPORTED_ENCODINGS = new HashSet ();
74 SUPPORTED_ENCODINGS.add("8859-1");
75 SUPPORTED_ENCODINGS.add("8859_1");
76 SUPPORTED_ENCODINGS.add("iso-8859-1");
77 SUPPORTED_ENCODINGS.add("ISO-8859-1");
78 SUPPORTED_ENCODINGS.add("iso8859_1");
79 SUPPORTED_ENCODINGS.add("ISO8859_1");
80 }
81
82 static boolean isSupportedEncoding(String encoding) {
83 return SUPPORTED_ENCODINGS.contains(encoding);
84 }
85
86 private ByteBuffer mBuffer;
87
88 private transient byte[] mTempBytes;
89 private transient char[] mTempChars;
90
91 private CharToByteBuffer mSlowConvertor;
92
93
96 public FastCharToByteBuffer(ByteBuffer buffer) {
97 this(buffer, null);
98 }
99
100
105 public FastCharToByteBuffer(ByteBuffer buffer, String defaultEncoding) {
106 mBuffer = buffer;
107 try {
108 setEncoding(defaultEncoding);
109 }
110 catch (IOException e) {
111 }
112 }
113
114 public void setEncoding(String enc) throws IOException {
115 drain();
116 if (isSupportedEncoding(enc)) {
117 mSlowConvertor = null;
118 }
119 else {
120 mSlowConvertor = new DefaultCharToByteBuffer(mBuffer, enc);
121 }
122 }
123
124 public String getEncoding() throws IOException {
125 return mSlowConvertor != null ?
126 mSlowConvertor.getEncoding() : "ISO-8859-1";
127 }
128
129 public long getBaseByteCount() throws IOException {
130 drain();
131 return mBuffer.getBaseByteCount();
132 }
133
134 public long getByteCount() throws IOException {
135 drain();
136 return mBuffer.getByteCount();
137 }
138
139 public void writeTo(OutputStream out) throws IOException {
140 drain();
141 mBuffer.writeTo(out);
142 }
143
144 public void append(byte b) throws IOException {
145 drain();
146 mBuffer.append(b);
147 }
148
149 public void append(byte[] bytes) throws IOException {
150 append(bytes, 0, bytes.length);
151 }
152
153 public void append(byte[] bytes, int offset, int length)
154 throws IOException
155 {
156 if (length != 0) {
157 drain();
158 mBuffer.append(bytes, offset, length);
159 }
160 }
161
162 public void appendSurrogate(ByteData s) throws IOException {
163 if (s != null) {
164 drain();
165 mBuffer.appendSurrogate(s);
166 }
167 }
168
169 public void addCaptureBuffer(ByteBuffer buffer) throws IOException {
170 drain();
171 mBuffer.addCaptureBuffer(buffer);
172 }
173
174 public void removeCaptureBuffer(ByteBuffer buffer) throws IOException {
175 drain();
176 mBuffer.removeCaptureBuffer(buffer);
177 }
178
179 public void append(char c) throws IOException {
180 char[] chars = getTempChars();
181 chars[0] = c;
182 append(chars, 0, 1);
183 }
184
185 public void append(char[] chars) throws IOException {
186 append(chars, 0, chars.length);
187 }
188
189 public void append(char[] chars, int offset, int length)
190 throws IOException
191 {
192 if (mSlowConvertor != null) {
193 mSlowConvertor.append(chars, offset, length);
194 return;
195 }
196
197 appendFast(chars, offset, length);
198 }
199
200 public void append(String str) throws IOException {
201 append(str, 0, str.length());
202 }
203
204 public void append(String str, int offset, int length) throws IOException {
205 if (mSlowConvertor != null) {
206 mSlowConvertor.append(str, offset, length);
207 return;
208 }
209
210 if (length == 0) {
211 return;
212 }
213
214 char[] tempChars = getTempChars();
215 int bufLen = tempChars.length;
216
217 while (length >= bufLen) {
218 str.getChars(offset, offset + bufLen, tempChars, 0);
219 offset += bufLen;
220 length -= bufLen;
221 appendFast(tempChars, 0, bufLen);
222 }
223
224 if (length > 0) {
225 str.getChars(offset, offset + length, tempChars, 0);
226 appendFast(tempChars, 0, length);
227 }
228 }
229
230 public void reset() throws IOException {
231 mBuffer.reset();
232 }
233
234 public void drain() throws IOException {
235 if (mSlowConvertor != null) {
236 mSlowConvertor.drain();
237 }
238 }
239
240 private void appendFast(char[] chars, int offset, int length)
241 throws IOException
242 {
243 byte[] tempBytes = getTempBytes();
244 int bufLen = tempBytes.length;
245 int bi = 0;
246 int climit = offset + length;
247
248 for (int ci = offset; ci < climit; ci++) {
249 tempBytes[bi++] = (byte)chars[ci];
250 if (bi >= bufLen) {
251 mBuffer.append(tempBytes, 0, bufLen);
252 bi = 0;
253 }
254 }
255
256 if (bi > 0) {
257 mBuffer.append(tempBytes, 0, bi);
258 }
259 }
260
261 private byte[] getTempBytes() {
262 if (mTempBytes == null) {
263 mTempBytes = new byte[TEMP_BUF_LEN];
264 }
265 return mTempBytes;
266 }
267
268 private char[] getTempChars() {
269 if (mTempChars == null) {
270 mTempChars = new char[TEMP_BUF_LEN];
271 }
272 return mTempChars;
273 }
274 }
275 |
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